AD	Alzheimer’s disease
AHR	aryl hydrocarbon receptor
AMPA	α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid
BBB	blood–brain barrier
EAARs	excitatory amino acid receptors
EPSPs	excitatory postsynaptic potentials
GABA	α-aminobutyric acid
GPR 35	G-protein-coupled receptor 35
HD	Huntington’s disease
5-HT2	5-hydroxy-triptamin-2 receptor
KYNA	kynurenic acid
KYN	kynurenine
KAT II	kynurenine aminotransferase II enzyme
L-KYN	L-kynurenine
LTP	long-term potentiation
NMDA	N-methyl-D-aspartate receptor
PD	Parkinson’s disease
PFC	prefrontal cortex
QUIN	quinolinic acid
Trp	Tryptophan